A Multiple Disk Probe for Inexpensive and Robust Velocimetry

Abstract

A novel velocimeter consisting of multiple orthogonal disks fitted with pressure transducers has been developed. Dynamic pressure differences are measured between the center of one disk face and the center of the other face, on each of the disks. While previously-developed anemometers based on dynamic pressure differences (such as yaw or three-hole probes) can only measure velocities with a small range of directions, the new disk probe can measure three components of velocity, even in highly three-dimensional flows where the approximate direction of the flow is not known. Wind tunnel tests have shown the velocimeter to be quite accurate; it can measure velocities to ±1.4% and wind directions to ±4 deg. The velocimeter is very robust and therefore can make measurements in environments too harsh for most other velocity transducers.